Preheat the oven to 350 degrees F and lightly grease a 9x9 baking pan.
In a large mixing bowl, toss the apples with lemon juice, white sugar, cornstarch, cinnamon, and vanilla. Transfer to the prepared baking pan, including all the juices.
In a separate medium-sized bowl or food processor, combine flour, brown sugar, and cinnamon. Use a pastry cutter or the food processor to blend in the cold butter until combined, ensuring some clumps remain.
Evenly spread the crumble mixture over the apples.
Bake in the preheated oven for 40-45 minutes, or until the crumble is golden brown.